Lethal Heating: 10/05/17

05/10/2017

More Daytime Images Of The Larsen C Iceberg Have Come In, And They're Amazing

Mashable - Andrew Freedman

Larsen C icebergs seen using a thermal imaging instrument aboard a NASA satellite. Image: NASA

In July, one of the largest icebergs ever recorded — measuring in at about the size of Delaware and containing a volume of ice twice the size of Lake Erie — broke off the Larsen C Ice Shelf in northwest Antarctica.
The event, which took place during the frigid blackness of the Antarctic winter, was detected using satellite instruments that could pierce the darkness to sense the ice below. As the austral spring dawns, scientists are now being granted their first glimpses of the new iceberg during the daytime.
And the images are incredible.
The first daytime satellite photo to be released by NASA came on Sept. 11, via an instrument on NASA's Terra satellite, which is known as the Moderate Resolution Imaging Spectroradiometer, or MODIS.
It revealed the massive iceberg, which dwarfs Manhattan yet somehow has taken on its shape, in all its glory.

Satellite image showing the massive Antarctic iceberg and its smaller sibling on Sept. 16, 2017. Image: NASA

Soon after, other NASA satellites, including Landsat 8, captured detailed images that NASA published on Sept. 30.
The new data shows how the massive iceberg has split into smaller pieces since it cleaved off from the floating ice shelf last summer, and reveals that it has begun to push away from the ice shelf that birthed it, thanks to offshore winds.
The original iceberg weighed about 1 trillion tons, according to a team of researchers affiliated with a U.K.-based research project, known as Project MIDAS. While the iceberg calving event itself is likely mostly natural, it nevertheless threatens to speed up the already quickening pace of ice melt in the region due in large part to global warming.

Iceberg A-68 drifting out to sea, posing a danger to ships.

In its original shape, the iceberg was about 2,200 square miles in area, Project MIDAS researchers said in a blog post on July 12. In late July, the main iceberg, known as A-68A, lost several chunks of ice as it began to slowly drift out to sea.
One of those large chunks is now known as A-68B, according to the National Ice Center, which tracks large icebergs because they pose a danger to ships.
Around the same time, scientists revealed that new cracks were developing on the Larsen C ice shelf, potentially signaling additional breakup events in the coming months to years.
Scientists are closely monitoring the Larsen C Ice Shelf because of the warming occurring in that region, and the unsettling history of other ice shelves in the area.

The icebergs in natural color (left). Thermal image (right) reveals where the colder ice ends and warmer water begins. Image: NASA

The Antarctic Peninsula, which is where the Larsen C Ice Shelf is located, is one of the most rapidly warming parts of the Earth. Two of its neighbors, Larsen A and Larsen B, have already collapsed. (The rapid breakup of Larsen B inspired the opening scene in the disaster flick, The Day After Tomorrow.)
Because of that history, there is tremendous scientific interest in seeing how Larsen C responds to losing about 12 percent of its area in a single, trillion-ton iceberg. While the iceberg calving event itself is not likely caused specifically by climate change, it nevertheless threatens to speed up the already quickening pace of ice melt in the region by leaving the ice shelf behind it in a weakened state, with new cracks that may develop additional icebergs in the future.
The melting of the ice shelf does not affect global sea levels directly, since the ice was already floating, like an ice cube in a glass, before the calving event. However, when ice shelves like Larsen C melt, they can free up land-based ice behind them to flow faster into the sea, which does raise sea levels.

WATCH: An iceberg the size of Delaware broke off Antarctica

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Climate Change Creating Food Shortages Across The Pacific, Says Support Agency

New Zealand Herald - Frances Cook

Islanders say warming oceans are affecting their main source of food - fish. Photo / 123rf

Food shortages and eroding coastlines are an increasingly urgent problem across the Pacific, thanks to climate change.
Caritas has just released Turning the Tide, its 2017 report on the state of the environment in Oceania.
Problems accessing safe food and drinking water were highlighted, with the increasing frequency of natural disasters making the problem more urgent.
"Our experience in 2016/17 is that it is becoming increasingly difficult to maintain the health and integrity of these sources [of local food supplies] - especially after a disaster," the report said.
"The poor are most affected when local supplies are disrupted - they often cannot afford to buy food and water from other sources."
George Alabeni from Arihu Rural Training Centre in Solomon Islands, told Caritas the sea was now becoming so hot, it was unpleasant.
"Before you just go down to the shore and might take fish and see a lot of seashells, crabs and the beauty of the sea; everything.
"There are birds all around the beach, very white beach.
"Now seabirds' coastal homes are being destroyed, and dead fish are washing up on shore.
"We don't expect it, and it's new to us. We have never seen those things happening."
Meanwhile those living in Tuvalu and Vanuatu had been forced to permanently change their diet after Cyclone Pam.
Climate justice advocate Aso Ioapo said locals hadn't been able to replant crops damaged by the storm surges and flooding of the 2015 disaster.
"Since the cyclone they have had to use more imported food, from stores, including chicken, meat, because our food was destroyed in the cyclone.
"Imported food is very new for us in our lives.
"We miss all of our local foods, because in Tuvalu they really need the fish every day ... you have breakfast, morning, lunch and dinner with the fish."
Caritas rated the impact of coastal erosion, flooding, and rising seas as "severe".
It said coastal flooding and sea level rise was displacing increasing numbers of people, especially around Papua New Guinea.
While Caritas acknowledged climate aid money was increasing, it said the funding still fell short of what was needed.
In particular it said that New Zealand "could be playing a pivotal role", yet "seems to be lagging and even reducing its commitments to the Pacific".
The organisation made a raft of recommendations, including a call for the global community to do more to help people who will lose their homes through climate change.
This includes a call to create legal protections for people who are forced to leave their country because of climate change, and putting together a regional body to map which communities are likely to be worst affected.
It's also pushing for the Australian and New Zealand governments to prioritise investments in agriculture, fisheries, and water sources that are climate resilient, to make sure Pacific communities have access to sustainable local sources.

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Sydney, Melbourne Urged To Prepare For 50c Days By End Of Century

ABC News - Jake Evans

The new study projects daily temperatures 3.8C above existing records for Sydney and Melbourne. (ABC News: Mary Lloyd)

Sydney and Melbourne have been warned to prepare for scorcher days reaching 50 degree Celsius by the end of the century — even if global warming is contained to the Paris Agreement target of a 2C increase.

A new study led by Australian National University (ANU) climate scientist Dr Sophie Lewis has projected daily temperatures 3.8C above existing records for the two cities and even hotter extremes.
"We have to be thinking now about how we can be prepared for large population groups commuting to and from the CBD on these extremely hot days, how we send young children to school on 50C days, how our hospitals are prepared for a larger number of admissions of young or old people, and how our infrastructure can cope with it," Dr Lewis said.
The study found containing global warming to 1.5C — the more ambitious target set by the Paris Agreement — would limit extreme heat, but Dr Lewis said angrier summers were inevitable.

"A lot of warming is locked into the climate system and we really have to be prepared for extremes in the future to get much worse than they are now," she said.

"We've already seen an increase in excess heat deaths in heatwaves in 2009, due to those extreme heatwaves, and that's likely to occur even more under these 50C days."
Pockets of Australia have tasted temperatures close to 50C, mostly remote country towns.
But Dr Lewis said heats like that would look very different in Sydney or Melbourne.

"In the city we have a lot more concrete and a lot less air flow, there's a lot less ability to escape from the heat," she said.

The ANU study only analysed Bureau of Meteorology data from Sydney and Melbourne, but Dr Lewis said all of Australia could expect to see hotter extremes in the future.

'It's not great news, obviously'
"It's not great news, obviously," Deputy Lord Mayor of Sydney Jess Miller said.

"We know that more people die from heat-related incidents than they do from bushfires each year. I think we're heading into a really scary health risk."

St Kilda Beach in Melbourne is already packed when the temperature climbs to 40C. (AAP/David Crosling)

Ms Miller said one of the issues facing Sydney and Melbourne was the emergence of "heat continents", where entire suburbs baked for a significant period of time without relief.
"When you've got grey infrastructure and roads and buildings absorbing all that heat, not only does it get much hotter, but it takes twice to three times as long to cool down," she said.
And Ms Miller said 50C days also posed a threat to city transport.
All Sydneysiders know the sense of dread as they pack into Central Station on a sweaty day, but Ms Miller said it was not only the commuters who would suffer if the temperature reached 50C.

"Public transport melts, literally, on really hot days," she said.

"When you have a bunch of days one by one, it stops the whole system."
Ms Miller said city planners needed to begin designing cities that took advantage of wind, green spaces and shade whilst still being cost-effective.
"We need to think of ourselves as part of the ecology of a city, and that a city is not just a bunch of buildings and roads," she said.

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